file-online-preview/server/src/main/java/cn/keking/service/impl/MediaFilePreviewImpl.java

package cn.keking.service.impl;

import cn.keking.config.ConfigConstants;
import cn.keking.model.FileAttribute;
import cn.keking.model.FileType;
import cn.keking.model.ReturnResponse;
import cn.keking.service.FilePreview;
import cn.keking.utils.DownloadUtils;
import cn.keking.service.FileHandlerService;
import cn.keking.web.filter.BaseUrlFilter;
import org.artofsolving.jodconverter.util.ConfigUtils;
import org.bytedeco.ffmpeg.global.avcodec;
import org.bytedeco.javacv.FFmpegFrameGrabber;
import org.bytedeco.javacv.FFmpegFrameRecorder;
import org.bytedeco.javacv.Frame;
import org.springframework.stereotype.Service;
import org.springframework.ui.Model;
import java.io.File;

/**
 * @author : kl
 * @authorboke : kailing.pub
 * @create : 2018-03-25 上午11:58
 * @description:
 **/
@Service
public class MediaFilePreviewImpl implements FilePreview {

    private final FileHandlerService fileHandlerService;
    private final OtherFilePreviewImpl otherFilePreview;

    private static Object LOCK=new Object();

    public MediaFilePreviewImpl(FileHandlerService fileHandlerService, OtherFilePreviewImpl otherFilePreview) {
        this.fileHandlerService = fileHandlerService;
        this.otherFilePreview = otherFilePreview;
    }

    @Override
    public String filePreviewHandle(String url, Model model, FileAttribute fileAttribute) {
        // 不是http开头，浏览器不能直接访问，需下载到本地
        if (url != null && !url.toLowerCase().startsWith("http")) {
            ReturnResponse<String> response = DownloadUtils.downLoad(fileAttribute, fileAttribute.getName());
            if (response.isFailure()) {
                return otherFilePreview.notSupportedFile(model, fileAttribute, response.getMsg());
            } else {
                url=BaseUrlFilter.getBaseUrl() + fileHandlerService.getRelativePath(response.getContent());
                fileAttribute.setUrl(url);
            }
        }

        if(checkNeedConvert(fileAttribute.getSuffix())){
            url=convertUrl(fileAttribute);
        }else{
            //正常media类型
            String[] medias = ConfigConstants.getMedia();
            for(String media:medias){
                if(media.equals(fileAttribute.getSuffix())){
                    model.addAttribute("mediaUrl", url);
                    return MEDIA_FILE_PREVIEW_PAGE;
                }
            }
            return otherFilePreview.notSupportedFile(model, fileAttribute, "暂不支持");
        }
        model.addAttribute("mediaUrl", url);
        return MEDIA_FILE_PREVIEW_PAGE;
    }

    /**
     * 检查视频文件处理逻辑
     * 返回处理过后的url
     * @return url
     */
    private String convertUrl(FileAttribute fileAttribute) {
        String url = fileAttribute.getUrl();
        if(fileHandlerService.listConvertedMedias().containsKey(url)){
            url= fileHandlerService.getConvertedMedias(url);
        }else{
            if(!fileHandlerService.listConvertedMedias().containsKey(url)){
                synchronized(LOCK){
                    if(!fileHandlerService.listConvertedMedias().containsKey(url)){
                        String convertedUrl=convertToMp4(fileAttribute);
                        //加入缓存
                        fileHandlerService.addConvertedMedias(url,convertedUrl);
                        url=convertedUrl;
                    }
                }
            }
        }
        return url;
    }

    /**
     * 检查视频文件转换是否已开启，以及当前文件是否需要转换
     * @return
     */
    private boolean checkNeedConvert(String suffix) {
        //1.检查开关是否开启
        if("false".equals(ConfigConstants.getMediaConvertDisable())){
            return false;
        }
        //2.检查当前文件是否需要转换
        String[] mediaTypesConvert = FileType.MEDIA_TYPES_CONVERT;
        String type = suffix;
        for(String temp : mediaTypesConvert){
            if(type.equals(temp)){
                return true;
            }
        }
        return false;
    }

    /**
     * 将浏览器不兼容视频格式转换成MP4
     * @param fileAttribute
     * @return
     */
    private static String convertToMp4(FileAttribute fileAttribute) {

        //说明：这里做临时处理，取上传文件的目录
        String homePath = ConfigUtils.getHomePath();
        String filePath = homePath+File.separator+"file"+File.separator+"demo"+File.separator+fileAttribute.getName();
        String convertFileName=fileAttribute.getUrl().replace(fileAttribute.getSuffix(),"mp4");

        File file=new File(filePath);
        FFmpegFrameGrabber frameGrabber = new FFmpegFrameGrabber(file);
        String fileName = null;
        Frame captured_frame = null;
        FFmpegFrameRecorder recorder = null;
        try {
            fileName = file.getAbsolutePath().replace(fileAttribute.getSuffix(),"mp4");
            File desFile=new File(fileName);
            //判断一下防止穿透缓存
            if(desFile.exists()){
                return fileName;
            }

            frameGrabber.start();
            recorder = new FFmpegFrameRecorder(fileName, frameGrabber.getImageWidth(), frameGrabber.getImageHeight(), frameGrabber.getAudioChannels());
            recorder.setVideoCodec(avcodec.AV_CODEC_ID_H264); //avcodec.AV_CODEC_ID_H264  //AV_CODEC_ID_MPEG4
            recorder.setFormat("mp4");
            recorder.setFrameRate(frameGrabber.getFrameRate());
            //recorder.setSampleFormat(frameGrabber.getSampleFormat()); //
            recorder.setSampleRate(frameGrabber.getSampleRate());

            recorder.setAudioChannels(frameGrabber.getAudioChannels());
            recorder.setFrameRate(frameGrabber.getFrameRate());
            recorder.start();
            while ((captured_frame = frameGrabber.grabFrame()) != null) {
                try {
                    recorder.setTimestamp(frameGrabber.getTimestamp());
                    recorder.record(captured_frame);
                } catch (Exception e) {
                }
            }
            recorder.stop();
            recorder.release();
            frameGrabber.stop();
        } catch (Exception e) {
            e.printStackTrace();
        }
        //是否删除源文件
        //file.delete();
        return convertFileName;
    }
}